Electric-brake controller



E. B. THURSTON.

ELECTRIC BRAKE CONTROLLER. APPLICATION FILED NOV, 29. 19l8.

1,435,565, Patented Nov. 14, 1922.

. 2 SHEETSSHEET l. FIG. 1-

FIE-5 E. B. THURSTON.

ELECTRIC BRAKE CONTROLLER. APPLICATION FILED NOV. 20,- l9l8,

Patented Nov. 14, 1922.

2 SHEETSSHEET 2.

residing at Toledo, Lucas, County,

Patented Nov. 141, 19221.

hilt

ERNEST BQTHURSTON, OF TOLEDO, OHIO, ASSIG-NOR TO THE HAUGHTON ELEVATOR &

MACHINE (30., OF TOLEDO, OHIO, A CORPORATION OF OHIO.

ELECTRIC-BRAKE CONTROLLER,

T0 all whom it may concern:

Be it known that I, ERNEST B. THuRsroN, a citizen of the United Statesof America, Ohio, have invented new and useful Electric-BrakeControllers, of which the following is a specification.

This invention relates to electric controlling mechanisms, especiallyfor alternating current circuits.

This invention has utility in connection with gradual current flowchange, particularly inassociation with aswitc'h, as in elevators.

Referring to the drawings:

Fig. 1 is a wiring diagram of an embodiment of the invention as a slowup-stop apparatusfor rendering more easy and accurate bringing of highspeed alternating current driven elevators under differing loads toproper landing positions;

Fig. 2 is an enlarged detail ofthe con troller; and Y Fig. 3 is a wiringdiagram, similar to Fig. 1, with supplemental retarding features in thecontrolling mechanism, as well as polyph ase adaptation thereof.

The alternating electric current motor 1 is mounted on drive shaft 2carrying brake,

drum 3 embraced by a pair of opposing brake shoes 4 normally thrust intoholding.

positionbya spring 5 to hold the member 3 as'a brake from rotation whenthe motor 1 is cut oil from driving. The shaft 2 carries agworm 6 inmesh with worm wheel 7 on shaft 8 carrying drum 9about which passeshoisting cable 10 extending down the elevator shaft to car 11, movabletovarious landings 12. The cable 10 in its opposite direction from thedrum 9,'passes about guide pulley-13 to counterweight 14.

In the car 11 is a controller or handle 15 for manual operation ineffecting car travels and stops. This controller 15 is pivotally mountedon the bearing 16 and carries a contact 17, which in normal upright orcentral position forthe handle 15, bridges be" tween terminals 18, 19connected by line 20.

Upon shifting the handle 15 to the right, the contact 17 moves away fromthe terminal 18, but so travels as to close circuit between terminals19, 21. In the electric cable to the car 11 is line 22 from the terminal19, extending past emergency or terminal safety -moves against terminals44, 45,

switch 23 to supply line 24. From the terminal 21 in the same flexiblecable to the car 11, extends line 25, past safety switch 26 to 0011127,and thence to terminal 28 to which supply l1ne29 extends. The coil 27'thus energizes the main switch for lifting con tacts 30, 31. The contact30 is thus moved to close circuit between that supply line 34 is line 35to the motor contact 31 moves against terminals 28, 36, to close circuittherebetween.

(As the handle 15 is shiftedstill further to the right, the contact 17,still against terminals 19, connected by line 38, past safety switch 39,

terminals 32, 33, so connected to power 1. Simultaneously the 21,'alsocomes'to terminal 37 to direction switch coil 40 connected by line 41 tothe terminal 28 for current flow with supply line 29. Considering thecoil 41 as forthe up direction switch, as thus energized, it liftscontacts 42, 43.- The contact 42 and power I current supply from theline 29, to the terminal 28, past contact 31, to the terminal 36, may behad by line 46 to the terminal 45, and thence by the contact 42, to theterminal of line 49 to the .motor the third line to the motor 1 isclosed for cur- .rent flow from the linev 24 by line 50 to ter- Themotor 1 is accord- 44,. for line 47 to terminal .48 and by way 1.Simultaneously from its brake holding means. The current i from thesupply line 29 by way of conductors 28, 31, 36, 46, 45, 42, to theterminal 44, may

'be'connected by line 54 to running brake switch coil 55,from whichextends line 56 to terminal 57, line 58, by way of conductors 52, 43,51, 50, to complete circuit from the supply line 24 in energizingtherunning brake switch coil 55 for lifting contacts 59,

'60. From the supply line 34, by way of conductors 33, 30, 32, a line61- extends to terminal 62 against which the contact 59 is thrown forcompleting the circuit through terminal 63. line 64 to coil 65 at brake1nag- .net 66, and thence by line 67 to terminal 63 abutted by contact60, also engaging ter- .minal 69 connected by line 70 to the terminal51, having the line 50 connect it with the supplyline 24. The third pathofthe circuit for the brake magnet 66, is fron'rthe power line 29, byWay of terminal 28, contact- 31, terminal 36,,linei7l, to brake coil 72connectedto the linef67. The brake magnet 66- is thus energized fordrawing together at the top against the throw out action of the" spring5, and so the brake shoes 4 are released from the brake din-m3 as themotor 1.

is started to move the elevator 11 upward.

As the elevator car-11 in its-travel ap proachestafloor or landing 12,the arm 15 mayibeiimoved centerW -ard, or to have its Contact 1 7 getawayfrom the terminal 37,

the" toil: 40l1is. de energized, and the motor 1 discontinuesits drivingaction; The running fbrake-switch coil 55' is also de-energized,changingthe stronger polyphase holding of thebrak'e during -runningofthe elevator as actuated by the motor- 1, to single' phase: bconductors" 29, 28, 31,36; 71,- 72, 65, 64, and from-the terminal 63 byline 7 3 toreactanee coil 74 of car carried magnet 7 5'1hav'ingitsmagnetic circuit resistance-varid byfltheshiftablemeans 7 6 changing'the aii gap therein, said means being shown asdirectly. connected to thehandle 15 for movement therewith.- 7 Fromthe coil 1 7 4 extends line 77-to the terminal (32,and-by conductors1621;:32, 30,233, to "supply line34, for the" main line switch coi 'l 27 is still energized: It'is t o benotedthe running-brake switch'coilfi55, when energized, has the con tact595short5out'the coil 7 4.

Wlien the handle 15' has shifted the conta'ctt 17 justl'clear'of theterminal 37,*it is still-(at quitean anglerfrom its'centralposition,.xandu the: laminated shiftable means 7 6 considerable-air gapin"themagnetic circuit ofithisusecOnd or car carried magnet. The single1 phase current -through the coil 1 7 4- is thus considerable and as ithis in series with thebrake magnet coils-'65, 72, the amperetlfe=inactive central position may be slowed up or hastened. by theoperator, and thereby the" current consumption of the coil 74 re dufced;This'treduction of thecurrent flow in the coil 74,..likewise reduces theampere turnsholding actionof the coils 65, 72, not by '-a-.step' by stepaction, but gradually, so

asi'rtliemagnetrt'ioweakens there is in like 'the polyphase holdingdurin car The. action of the coil 1 74 tends to rate a holding of theshoes 4 by the spring 5 against the drum 3 to preclude overhauling' ofthe motor by the traveling cart In practice this means, the operator mayhave a highspeed traveling alternating current driven elevator withheavy or light load, and upon shutting ofiof the actuating motor,thehandle15 may be so shifted as to gradually apply the shoes 4, andthus Without any jerking orconeussion bring the car smoothly and easilyto an accurate landing position. When the contact 17 is moved centerwardaway from the terminal 21, the main switch coil 27 isde energized an'dcnr-- rent flowi isthus'entirelyout ofii'*-from-the'= coils 74, and65,72, I

For efi'ectingdownward-travel of theoar 11, opposite shifting of thecontioller han dle 15' is had. As the 'contact 17 moves away from-theteriii-inal'19, currentffiow for energizing the main switch (1011 27- issup-" plied,'-by the contact 17 now extending to terminal 78', connectedbyline 7 9' t'o'the ter-' minal 19; The further-shifting of' thecontroller handle 15 for reversing two of'the power lines to themotor"1,- and thuschanging "its direction of driving rotation, bringsthe'contact 17 to terminal8O,- havingline 81 extendingpast safety switch82"t o tlown wardtravel direction 1 switch coil'83". The energized coil83, has its circuit completed by line 84, andby Way of conductorsh41;28, to the supply 1ine 29.-

The coil 83 lifts contacts 85, 86. *The con tact 85 efiectsclosin'g'ofpowencircuit froin the linev24, by conductors 50,- 5:1", andaline' 87to the terminal 88, i and from thencei by. the terminal 48 and the line49 to the motor 1. The contact '86 effects closing ofi'povver circuitfrom the line-. 29 bly conductors'28, 31, 36, 46, 45, andaline 8.9 toterminaLQO, and from thence =hy'the terminal57, line=58,l

terminal x52, and the line 53"to"the motor '1;

Simultaneously with: the supply of 'powerr' current to the motor 1,rthewelectromagnetic brake is released, as described'in connection withtheup-travelof the-canll. In the...-

shutting off of driving power for stopping the descending car 11, themovement'fofithe handle 15 away from the terminal1 81, testablishes thesame conditions. for single: phase switch, as is possible:in theascendingrcar,' forltheterminals 7 8 and 21 are connected.

There may bean interlocking control in brake holding, witlicmanuallycontrollable dwindlingcurrenta" to full shnt ofii of: the

the apparatusfor rlagging. or; retarding'the full action of therunningbrake switch so the lcar' 11 may travel Without"brake' inteiference for a distance,'.'shouldsuch" be desired, as shown inFig. 3.Here the shifting; of the controller contact 17 to the terminal 21:60111160138111)"the- 11116:25 past switchr26, toterminal91,-iconnected'by line592. to terminal 93, which V latter" isconnected 'by. line 94 to terminal 95. There is thus far no energizingof any coil, and accordinglyno throw of any remote controlled switch.

The further shifting of the controller con-- tact 17 to the terminal 37,connects up the line 38, past the switch 39, to the up-direction coil40. This lifting of the contacts 42,

43, also lifts contact 96, "for shorting between the terminal 93 currentflow by way of line 98, terminal 99, and line 100 to energize the coil27, and thereby giving a retarding closing of the main line switch as tothe direction switch. Besides completion of the power brake circuits forupward travel of occurs from the lifting of the switch by the coil 27, amovement of contact 101 for shorting between the terminals 91, 99. Thisinsures a holding of the main line switch in after the controllercontact 17 has left the terminal 3? for shutting ofi driving actua: tionof the motor 1. The retarded throwing in of the main line switch by thecoil 27 on starting, precludes other than quick release of the shoes 4from the drum 3, as the motor 1 takes hold for driving operation.

Accordingly for stopping the upward travel of the car 11, the movementof the controller contact 17 off the terminal 37 cuts out the motor fromdriving, but does not directly apply the brake thereto. The momentum ofthe traveling parts may thus be spent in slowing up the car, and theduration of the slowing up may be limited manually by completing thethrow of the controller 17 to clear the contact 21. In practicehereunder this handling of converting the brake from polyphase to singlephase and then further reducing the holding action by graduallyweakening the single phase holding, has been worked out with no chattertrouble. The downward travel is analogousto that for lifting, but inenergizing the coil 83 by circuit from controller terminal 80, downswitch coil 83, lifts with the contacts 85,86, a contact 102, shortingbetween the terminal 95 and terminal 103, connected by line 104 to theterminal 97, for circuit completion to the main switch coil 27 as in theup travel.

While this diagram as described in its application to Fig. 3 may becomplete and fully operative, additional wiring is shown therein foroperating the brake magnet as polyphase during its dwindling beforebeing switched off, and this is accomplished by the provision of anadditional coil 105 adjacent the coil 74, coacting therewith as thecoils 65, 72 coact at the brake magnet, for with the two coils at thebrake there is more uniform pull, and likewise the pull at thecontroller is more uniform with the two coils than with the one. Lines106, 107, from the coil 105 extend respectively to the terminals 68, 69,to have the circuit from supply and terminal 97 for the car 11, thereline 24 therethrough shorted for cutting out the coil 105 when therunning brake'switch coil 55 is energized, by the contact 60 actingbetween these terminals 68, 69, in a manner analogous to the action ofthe contact 59 as to the coil 74. Accordingly in the installa tionhaving coils 105 and 74 for the reactance or air gap varying means 76,there is no pulling 0E ofthe brake magnet coils 65, 72, from polyphaseto single phase, but the weakening is gradual. There is more currentthrough the coils 105, 74, as the controller contact 17'leaves theterminal 80 or the terminal 37 in its movement toward switch cutting outor central position, and this current is uniformly reduced until onlyacting as single phase, with no abrupt change. The electromagneticholding of the shoes 4 off the drum 3, thus allows the springs togradually come into full braking position after the motor 1 discontinuesdriving action. There is further no trouble from possible brakechattering due to this polyphase action throughout.

. With a minimum of mechanical complication, there is provided herein bysimple electric controlling mechanism the maximum range of slowing up orflexibility in power control from a maximum to full cutting off. Thisopens up the fields of high linear travel rate and first class passengertravel installations of elevators to alternating current electricoperation with quiet operation at all times for quick accurate stoppingwithout bumping or jerking in responding to the most exactingrequirements.

Vhat is claimed and it is desired to secure by Letters Patent is:

1. An elevator, a brake therefor, means normally setting the brake intoelevator holding position, acoil for releasing the brake against theaction of the brake holding means, motor for the elevator. a controllerfor the motor, a coil at the controller in series with the brake coil,and means shiftable with the controller in movement toward off positionto act upon the controller coil for decreasing current flow therethroughthereby to reduce the holding action of the brake coil.

2. A brake, means normally setting the brake, a coil for releasing thebrake against the action of the brake setting means, a controller fordeenergizing the brake coil, and means shiftable with the controller inits deenergizing direction travel reducing the current in the brake coilbefore cutting out said coil.

3. A brake. means normally setting the brake, a coil for releasing thebrake against the action of the brake setting means, a controller fordeenergizing the brake coil, a

brake switch operable for energizing the coil and affected by thecontroller for deenergizing the brake coil, and means shiftable with thecontroller in its deenergizing direction travel reducing the currentin=thebrake coil before cutting out said 0011;

4. Gradual settlng meansfor an electromagnetic brake for an elevatorembodying a coil for energizing the brake into releasing position forthe brake, and an elevator controller having an armature and a coil inanormally set brake, a coil for re-- leasing the brake, a switch forcutting 1n the b-rake'coil, e' controller" for the brake coil,-

as the controller opens the brake coil switch to operate said controllercoil'in series with the brake coil as an increasing resistance forgradually reducing the holding action of the-'brakecoi-l in slowing upthe application of the brake.

In Witness whereof I afiix my signature ERNEST B; THURSTON. 1

